From: Ben Cahill <ben.m.cahill@xxxxxxxxx>
Invoke workaround to avoid instability in L0->L0S->L1 transition on PCIe bus.
Workaround disables L0S state so device moves directly from L0->L1.
Workaround needed on all devices since and including 4965; add to 6000/1000.
Describe bug and workaround better in comments.
Signed-off-by: Ben Cahill <ben.m.cahill@xxxxxxxxx>
Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
drivers/net/wireless/iwlwifi/iwl-1000.c | 4 ++--
drivers/net/wireless/iwlwifi/iwl-6000.c | 20 ++++++++++----------
drivers/net/wireless/iwlwifi/iwl-core.c | 8 ++++++--
3 files changed, 18 insertions(+), 14 deletions(-)
diff --git a/drivers/net/wireless/iwlwifi/iwl-1000.c b/drivers/net/wireless/iwlwifi/iwl-1000.c
index 3a645e4..1e387b9 100644
--- a/drivers/net/wireless/iwlwifi/iwl-1000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-1000.c
@@ -164,7 +164,7 @@ struct iwl_cfg iwl1000_bgn_cfg = {
.valid_tx_ant = ANT_A,
.valid_rx_ant = ANT_AB,
.pll_cfg_val = CSR50_ANA_PLL_CFG_VAL,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.max_ll_items = OTP_MAX_LL_ITEMS_1000,
.shadow_ram_support = false,
@@ -190,7 +190,7 @@ struct iwl_cfg iwl1000_bg_cfg = {
.valid_tx_ant = ANT_A,
.valid_rx_ant = ANT_AB,
.pll_cfg_val = CSR50_ANA_PLL_CFG_VAL,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.max_ll_items = OTP_MAX_LL_ITEMS_1000,
.shadow_ram_support = false,
diff --git a/drivers/net/wireless/iwlwifi/iwl-6000.c b/drivers/net/wireless/iwlwifi/iwl-6000.c
index 32466d3..2f841a8 100644
--- a/drivers/net/wireless/iwlwifi/iwl-6000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-6000.c
@@ -299,7 +299,7 @@ struct iwl_cfg iwl6000h_2agn_cfg = {
.valid_tx_ant = ANT_AB,
.valid_rx_ant = ANT_AB,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_HYBRID,
.max_ll_items = OTP_MAX_LL_ITEMS_6x00,
@@ -329,7 +329,7 @@ struct iwl_cfg iwl6000h_2abg_cfg = {
.valid_tx_ant = ANT_AB,
.valid_rx_ant = ANT_AB,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_HYBRID,
.max_ll_items = OTP_MAX_LL_ITEMS_6x00,
@@ -358,7 +358,7 @@ struct iwl_cfg iwl6000h_2bg_cfg = {
.valid_tx_ant = ANT_AB,
.valid_rx_ant = ANT_AB,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_HYBRID,
.max_ll_items = OTP_MAX_LL_ITEMS_6x00,
@@ -390,7 +390,7 @@ struct iwl_cfg iwl6000i_2agn_cfg = {
.valid_tx_ant = ANT_BC,
.valid_rx_ant = ANT_BC,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_INTERNAL,
.max_ll_items = OTP_MAX_LL_ITEMS_6x00,
@@ -420,7 +420,7 @@ struct iwl_cfg iwl6000i_2abg_cfg = {
.valid_tx_ant = ANT_BC,
.valid_rx_ant = ANT_BC,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_INTERNAL,
.max_ll_items = OTP_MAX_LL_ITEMS_6x00,
@@ -449,7 +449,7 @@ struct iwl_cfg iwl6000i_2bg_cfg = {
.valid_tx_ant = ANT_BC,
.valid_rx_ant = ANT_BC,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_INTERNAL,
.max_ll_items = OTP_MAX_LL_ITEMS_6x00,
@@ -478,7 +478,7 @@ struct iwl_cfg iwl6050_2agn_cfg = {
.valid_tx_ant = ANT_AB,
.valid_rx_ant = ANT_AB,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_SYSTEM,
.max_ll_items = OTP_MAX_LL_ITEMS_6x50,
@@ -508,7 +508,7 @@ struct iwl_cfg iwl6050_2abg_cfg = {
.valid_tx_ant = ANT_AB,
.valid_rx_ant = ANT_AB,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_SYSTEM,
.max_ll_items = OTP_MAX_LL_ITEMS_6x50,
@@ -537,7 +537,7 @@ struct iwl_cfg iwl6000_3agn_cfg = {
.valid_tx_ant = ANT_ABC,
.valid_rx_ant = ANT_ABC,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_SYSTEM,
.max_ll_items = OTP_MAX_LL_ITEMS_6x00,
@@ -567,7 +567,7 @@ struct iwl_cfg iwl6050_3agn_cfg = {
.valid_tx_ant = ANT_ABC,
.valid_rx_ant = ANT_ABC,
.pll_cfg_val = 0,
- .set_l0s = false,
+ .set_l0s = true,
.use_bsm = false,
.pa_type = IWL_PA_SYSTEM,
.max_ll_items = OTP_MAX_LL_ITEMS_6x50,
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index 9e71544..2952890 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -1431,8 +1431,12 @@ int iwl_apm_init(struct iwl_priv *priv)
CSR_HW_IF_CONFIG_REG_BIT_HAP_WAKE_L1A);
/*
- * HW bug W/A - costs negligible power consumption ...
- * Check if BIOS (or OS) enabled L1-ASPM on this device
+ * HW bug W/A for instability in PCIe bus L0->L0S->L1 transition.
+ * Check if BIOS (or OS) enabled L1-ASPM on this device.
+ * If so (likely), disable L0S, so device moves directly L0->L1;
+ * costs negligible amount of power savings.
+ * If not (unlikely), enable L0S, so there is at least some
+ * power savings, even without L1.
*/
if (priv->cfg->set_l0s) {
lctl = iwl_pcie_link_ctl(priv);
--
1.5.6.3
--
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